Rotary cutter device

ABSTRACT

A rotary cutter device comprising a rotary cutter blade having a straight edge normal to the direction in which is fed or advanced a paper to be cut off and a stationary cutter blade having a curved edge inclined relative to said first mentioned edge upon a cylindrical surface generated by the rotation of said rotary cutter blade, the peripheral speed of said edge of said rotary cutter blade being maintained same with the speed of advancing the paper. The cutting line remains always at right angle relative to the direction of paper advancement even if the paper feed speed is varied.

United States Patent inventors Yugoro Kobayashi;

Tsutomu Yamakami, both of Tokyo, Japan 807 .026

Mar. 13, 1969 June 8, 1971 Kabushiki Kaisha Ricoh Tokyo, Japan Mar. 19, 1968 Japan Appl. No. Filed Patented Assignee Priority ROTARY CUTTER DEVICE 5 Claims, 2 Drawing Figs.

US. Cl 1. 83/341, 83/349 Int. Cl B26d 1/38 Field of Search ..83/34l, 349

[56] References Cited UNITED STATES PATENTS 3,073,196 1/1963 Marcalus... 83/341 3,080,781 3/1963 Spices i. 83/341X 3,264,921 8/1966 Nystrand 83/349X FOREIGN PATENTS 87,220 8/1936 Sweden 83/349 Primary Examiner-William S. Lawson Attorney-Burgess, Ryan and Hicks ABSTRACT: A rotary cutter device comprising a rotary cutter blade having a straight edge normal to the direction in which is fed or advanced a paper to be cut off and a stationary cutter blade having a curved edge inclined relative to said first mentioned edge upon a cylindrical surface generated by the rotation of said rotary cutter blade, the peripheral speed of said edge of said rotary cutter blade being maintained same with the speed of advancing the paper. The cutting line remains always at right angle relative to the direction of paper advancement even if the paper feed speed is varied.

PATENTED JUN 8l97l ROTARY CUTTER DEVICE BACKGROUND OF THE INVENTION The present invention relates to a rotary cutter and more particularly to a rotary cutter for use with a photocopying machine for cutting off photocopying paper.

In case of a photocopying machine of the type incorporating therein a rolled photocopying paper for the purpose of speeding up and automation of photocopying operation, it is required to cut off into a predetermined length the beltlike rolled photocopying paper. In this case, under the conventional practice, a guillotine cutter is used so that the paper must be stopped stationarily whenever it is cut off. Consequently, the paper advancement or feed is intermittently effected so that the continuous photocopying operation can not be attained. It might be possible to cut ofi the paper by the guillotine cutter without stopping the paper, but in this case, the cutter must be advanced or displaced together with the paper at the same speed with the paper advancing or feed speed. When these two speeds are not exactly equal, that is when there exists a relative speed therebetween the paper will not be cut off along a cutting line at right angle relative to the direction of the paper advancement. The papers are this cut off along the slanting lines. From the standpoint of the mechanism it is very difficult to vary the moving speed of the guillotine cutter in response to the paper feed speed so that so far no attempts have been successful. Therefore, the guillotine type movable cutter may be applied only when the paper is ad vanced at a constant speed, but will not be applied in a photocopying machine machine in whichfithe speed of paper advancementis inevitably varied.

The rotary cutter device has been already employed for cutting beltlike paper, but the peripheralspeed of the rotary cutter'blade is not'equal with the'paperfeeds'pee'd so that the rotary cutter blade is not positioned at right angle relative'to the paper feed direction, but at a certain inclined angle. Therefore, the rotational speed of the rotary cutter must remain in a predetermined constant relation with the paper feed speed so that the rotary cutter device of the typedescribed is employed generally only when the paper feed speed is constant.

The primaryobject'of'the present invention is therefore to provide a rotary cutterdevice which ensures always the accurate paper cutting-along-acutting lineatrightangle"relativeto the paper feed direction regardless of the variationof the paper feed speed and without'the neces sityofstopping the ad vancement of the paper to becut off.

SUMMARY OF THElNV-ENTION' blade, theperipheral speed of 'said ed'ge of said rotary cutten blade being maintained the same withthespeedof advancing.

theipaper to becutoff. Therefore, regardless thespeedofadvancing theipaper'to becut off, the 'cuttin'gsli'ne remains co'n-' stantly at a right angle relative to the aper advancing direction.

The aboveandoth'er objects, features and-advantages of the present invention will'becomc more apparent from the following description taken in' conjunction"-with'-theaccompanying drawing.

BRlEF DESCRlP TlONOF DRAWlNG FIG. I is a' -perspective'view of one=emboditnent of-arotary cutter device according to the present invention; and

FIG. 2 is 'aschematiesideview=thereof incorporated ina' photocopying machine.

such as diazo-typ'e duplicating DESCRlPTlON OF THE PREFERRED EMBODIMENT Referring particularly to FIG. I, a supporting plate 3 is welded to a rotary shaft 2 of a rotary cutter l and a rotary cutter blade 4 is fixedly secured upon this supporting plate 3. The rotary shaft 2 is rotated in the direction indicated by the arrow 5 by means of a suitable prime mover means not shown. In this case, the curve traced by the edge of the cutter blade 4 is a cylindrical surface shown by broken lines. The edge of the rotary cutter blade 4 is in parallel with the axis of the cylindrical surface so that the edge of the cutter blade 4 is a straight edge positioned along the generating line of the cylinder.

A stationary cutter blade 8 is fixedly secured to a supporting member 7 of the stationary cutter generally designated in its entirety by 6. The edge 9 of the stationary cutter blade 8 extends over the above described cylindrical surface and forms a curved cutter edge with respect to the straight edge of the rotary cutter blade 4. The paper is fed in the direction indicated by the arrow 10 and the feed velocity is made equal to the peripheral speed of the edge of the rotary blade 4.

The edge of the rotary cutter blade 4 and the edge 9 of the stationary cutter blade 8 are so arranged as to contact with each other when the rotary cutter l is rotated. The cutting edge 9 can be relieved by springs 14 and shown in FIG. 2. Alternatively, the edge 9 can be made thinner so as to utilize its elasticity in relieving the edge 9. The edge of the rotary cutter blade 4 contacts first with the edge 9 at point A thereof, and the contact point is being shifted toward point B along the edge 9 as the rotary blade 4 is rotated so that the edge of the rotary blade 4 and the edge 9 of the stationary cutter blade 8 remains always in contact relation with each other. Consequently, the paper fed in the direction indicated by the arrow [0 is successively cut' from one side of the paper to the other side at a right angle to the direction of feed of the paper.

As described hereinabove, since the paper is successively out while the both of the edges of the cutter blades make a point contact, the load applied to the cutter blades in paper cutting can be reduced so that the blades are prevented from being damaged and better cuts are provided in papers. In this case, it is preferable that the cutting angle remains unchanged at thecontact-poi'ntsof the edges of the cutter blades so that a uhiform cutting load as well as uniform cuts are ensured.

Referring to FIG. 2, the supporting member 7 of the stationary cu'ttc'r'6 is 'pivotably carried on a shaft 11 indicated by abroken'line. Thesupportingmember 7 has imparted thereto a torque tocause the supporting member 7 to rotate in the clockwise' directionabout theshaft 11 by means of bolts 12 and 13"threadablyfixed to the'supporting-mernbe'r andsprings l4an'd 'l s th'e ends ofwhich arefixedto'the bolts respectively and the-other ends-of which are fixed'toasupporting plate 16 which in turn is fixed to' the casing of the photocopying machine-Q'Upon the's'upporting-plate 16 is disposed an adjusting plate l8whic'h is'secured to the supportingmernber 7 and whoseposition can'be adjusted by an 'adjustingscrew 17. The

stationarycutter 6which'has'impa'rted thereto a tendency of I rotating in the clockwise direction'bythe'springs Hand 13 can' be-adjusted by screw 17 so that the edge 9 of the'rotary blade-*8is' suitably adjusted. Reference'numerals19, 20'and 21 denote-guide platesforphotocopyingpaperwhich is advanced into thisro'tarycutter device-in the direction indicated by the arrow Hand is discharged therefrom in thedirection indicated bythe arrow 23.

Paper *feedrollers 24 and 25 aredisposedat a position ad-' jacent theguide platesl9and 20'andat a position'adjacent to th'e'-g'uide*plates 'l9'and 21, and are driven through a drive roller 2-7 'through a'belt 26. In this case, therotation' of the of the edge of therotaryblade4'become equal. The gear '31 is drivingly coupled with an electromagnetic clutch (not shown) which is controlled by a device (not shown) for measuring the length of photocopying paper.

The rotary cutter blade 4 of the rotary cutter is normally held in a predetermined position when not operated. When the above described paper length measurement instrument is not actuated for measurement of the photocopying paper, the electromagnetic clutch is not actuated so that the rotation of the drive roller 24 is not transmitted to the rotary cutter l. Upon actuation of the measuring device and consequently the electromagnetic clutch, the rotation of the drive roller 24 is then transmitted to the rotary cutter shaft 2 so that the rotary blade 4 starts to rotate from the above described predetermined initial position, whereby the photocopying paper is cut off at the point of contact between the edge 9 of the stationary blade 8 and the edge of the rotary blade 4.

The peripheral speed of the edge of the rotary blade 4 is equal to the paper feed speed as described hereinabove, and there is no relative speed between the edge of the rotary blade 4 and the paper being fed and cut off during the cutting operation. Furthermore, since the edge of the rotary blade is positioned at a right angle relative to the paper feed direction, the paper is cut off along the straight line at a right angle to the paper feed direction. This is true even if the paper feed speed is varied because in this case the peripheral speed of the edge of the rotary blade 4 is also varied accordingly so that the relative relation between the paper and the edge of the rotary blade remains unchanged. Furthermore because of the equal peripheral speeds of the edge of the rotary blade 4 and the paper feed speed and because the edge of the rotary blade 4 is located always at the same inoperative initial position as described above, the length of the paper to be cut off remains the same regardless of the variation in the paper feed speed.

So far the present invention has been described with particular reference to one embodiment thereof which is applied to the photocopying machine. It is, however, to be understood that the present invention is not limited thereto, but can be advantageously applied to a cutting device for cutting rolled paper into sheet papers, especially a device in which the paper feed speed is inevitably varied.

lclaim:

l. A rotary cutter device for cutting a strip of sheetlike material along a cutting line extending perpendicular to the side of said strip, said device comprising a continuous rotary cutter blade having an axis of rotation and a rotary blade edge extending parallel to said axis of rotation, said rotary blade edge sweeping out a blade path in the form of a right circular cylinder during rotation of the rotary cutter blade;

guide means for guiding the strip along a strip path, a

cutting segment of said strip path coinciding with a portion of the blade path and being flanked by an approach segment of the strip path along which a strip may approach the cutting segment in a direction perpendicular to the axis of rotation and a recession segment along which a strip may recede from the cutting segment, said guide means comprising a pair of spaced guide plates defining between them the approach segment of the strip path;

a stationary cutter;

a continuous stationary cutter edge on the stationary cutter, said stationary cutting edge when in a cutting position coinciding with the cutting segment of the blade path and extending from one side of the strip path to the other, said stationary cutting edge extending at all segments along its length in a direction which is non-parallel to the axis of rotation of the rotary cutter blade;

and feed means for feeding a strip along the strip path at a speed equal to the peripheral speed of the rotary blade edge during engagement of said rotary blade edge with the strip.

2. The device of claim 1 wherein the convex side of the cutting portion ot" the strip path is at least partially defined by the stationary cutter and the concave side of the cutting portion of the strip path during the advance of the strip prior to a cutting operation is free of moving support elements, g

3. The device ofclaim 1 comprising support means fo r supporting the stationary cutter edge for motion away from the cutting position and biasing means for resiliently biasing the cutter edge into the cutting position.

4. The device of claim 3 wherein the support means comprises pivot means about which the stationary cutter can rotate and the biasing means comprises a spring extending between the stationary cutter and a fixed part of the device.

5. A rotary cutter device for cutting a strip of sheetlike material along a cutting line extending perpendicular to the side of said strip, said device comprising a rotary cutter blade having an axis of rotation and a rotary blade edge extending parallel to said axis of rotation, said rotary blade edge sweeping out a blade path in the form of a right circular cylinder during rotation of the rotary cutter blade;

guide means for guiding the strip along a strip path, a

cutting segment of said strip path coinciding with a portion of the blade path and being flanked by an approach segment of the strip path along which a strip may approach the cutting segment in a direction perpendicular to the axis of rotation, said approach segment being defined by a pair of spaced guide plates, and a recession segment along which a strip may recede from the cutting segment, the convex side of the cutting portion of the strip path being at least partially defined by a stationary cutter and the concave side of the cutting portion of the strip path during the advance of the strip prior to a cutting operation is free of moving support elements;

a stationary cutter edge on the stationary cutter, said stationary cutting edge when in a cutting position coinciding with the cutting segment of the blade path and extending from one side of the strip path to the other, said stationary cutting edge extending at all segments along its length in a direction which is nonparallel to the axis of rotation of the rotary cutter blade;

support means comprising pivot means about which the stationary cutter can rotate for supporting the stationary cutter edge for motion away from the cutting position;

biasing means comprising a spring extending between the stationary cutter and a fixed part of the device for resiliently biasing the cutter edge into the cutting position; and

feed means for feeding a strip along the strip path at a speed equal to the peripheral speed of the rotary blade edge during engagement of said rotary blade edge with the strip, said feed means comprising a rotatable drive roller positioned to engage a strip in the approach segment of the strip path and means for synchronizing the rotation of said feed roller with the rotation of the rotary cutter during motion of the rotary cutter blade in the cutting segment of the strip path and thereby producing identical peripheral speeds of the drive roller and the rotary cutter blade. 

1. A rotary cutter device for cutting a strip of sheetlike material along a cutting line extending perpendicular to the side of said strip, said device comprising a continuous rotary cutter blade having an axis of rotation and a rotary blade edge extending parallel to said axis of rotation, said rotary blade edge sweeping out a blade path in the form of a right circular cylinder during rotation of the rotary cUtter blade; guide means for guiding the strip along a strip path, a cutting segment of said strip path coinciding with a portion of the blade path and being flanked by an approach segment of the strip path along which a strip may approach the cutting segment in a direction perpendicular to the axis of rotation and a recession segment along which a strip may recede from the cutting segment, said guide means comprising a pair of spaced guide plates defining between them the approach segment of the strip path; a stationary cutter; a continuous stationary cutter edge on the stationary cutter, said stationary cutting edge when in a cutting position coinciding with the cutting segment of the blade path and extending from one side of the strip path to the other, said stationary cutting edge extending at all segments along its length in a direction which is non-parallel to the axis of rotation of the rotary cutter blade; and feed means for feeding a strip along the strip path at a speed equal to the peripheral speed of the rotary blade edge during engagement of said rotary blade edge with the strip.
 2. The device of claim 1 wherein the convex side of the cutting portion of the strip path is at least partially defined by the stationary cutter and the concave side of the cutting portion of the strip path during the advance of the strip prior to a cutting operation is free of moving support elements.
 3. The device of claim 1 comprising support means for supporting the stationary cutter edge for motion away from the cutting position and biasing means for resiliently biasing the cutter edge into the cutting position.
 4. The device of claim 3 wherein the support means comprises pivot means about which the stationary cutter can rotate and the biasing means comprises a spring extending between the stationary cutter and a fixed part of the device.
 5. A rotary cutter device for cutting a strip of sheetlike material along a cutting line extending perpendicular to the side of said strip, said device comprising a rotary cutter blade having an axis of rotation and a rotary blade edge extending parallel to said axis of rotation, said rotary blade edge sweeping out a blade path in the form of a right circular cylinder during rotation of the rotary cutter blade; guide means for guiding the strip along a strip path, a cutting segment of said strip path coinciding with a portion of the blade path and being flanked by an approach segment of the strip path along which a strip may approach the cutting segment in a direction perpendicular to the axis of rotation, said approach segment being defined by a pair of spaced guide plates, and a recession segment along which a strip may recede from the cutting segment, the convex side of the cutting portion of the strip path being at least partially defined by a stationary cutter and the concave side of the cutting portion of the strip path during the advance of the strip prior to a cutting operation is free of moving support elements; a stationary cutter edge on the stationary cutter, said stationary cutting edge when in a cutting position coinciding with the cutting segment of the blade path and extending from one side of the strip path to the other, said stationary cutting edge extending at all segments along its length in a direction which is nonparallel to the axis of rotation of the rotary cutter blade; support means comprising pivot means about which the stationary cutter can rotate for supporting the stationary cutter edge for motion away from the cutting position; biasing means comprising a spring extending between the stationary cutter and a fixed part of the device for resiliently biasing the cutter edge into the cutting position; and feed means for feeding a strip along the strip path at a speed equal to the peripheral speed of the rotary blade edge during engagement of said rotary blade edge with the strip, said feed means comprising a rotatable drive roller positioned to engage a strip in the approach segment of the strip path and means for synchronizing the rotation of said feed roller with the rotation of the rotary cutter during motion of the rotary cutter blade in the cutting segment of the strip path and thereby producing identical peripheral speeds of the drive roller and the rotary cutter blade. 